Aden is considered Yemen’s temporary capital, as the Saudi-backed Yemeni government has based itself there since 2015.

During the past two years, terrorist groups such as the al-Qaida in the Arabian Peninsula (AQAP) and the IS, had an active presence in the southern part of Yemen.

The impoverished Arab country has been locked into a civil war since 2014, when the Iranian-backed Shiite Houthi rebels overran much of the country militarily and seized all northern provinces, including the capital Sanaa.

Meanwhile, Saudi Arabia is leading an Arab military coalition which intervened in Yemen in 2015 to support the government of President Abd-Rabbu Mansour Hadi after Iran-backed Houthi rebels forced him into exile.